There are a variety of applications for radar systems, including use in connection with automated navigation (e.g. guiding of an airborne object, guiding of a vehicle, etc.). Generally, a radar system includes a transmitter and a receiver, where the transmitter is configured to emit a radar signal and the receiver is configured to receive at least a portion of the radar signal responsive to the radar signal reflecting from a target. Based upon time of flight of the radar signal, the radar system can identify a distance between the radar system and the target (as well as a rate of change of the distance between the radar system and the target). Additionally, a radar system can be used to track objects, identify objects, search for movement, search for a particular type of object, etc.
A pulsed radar system utilizes pulse timing techniques to, for example, determine the range to a target. In operation, the transmitter emits pulses of radio energy, each of which has pulse width (in time). It has been found that radar system performance increases if the pulse width is a function of a distance between the radar system and the target, where the further the target is away from the radar system, the larger the pulse width.
On the radar receiver, conventionally, filters are employed to enhance a signal-to-noise ratio (SNR) of a detected radar pulse. Typically, the bandwidth of the filter (the size of the passband) is designed to correspond to the narrowest pulse that can be emitted by the radar transmitter. This is suboptimal, however, as unwanted noise may pass through the filter when the radar transmitter emits pulses with larger widths.